They sure do now, but not back in 1964. :-)
paul
> On Apr 22, 2024, at 5:13 PM, Mike Katz via cctalk <[email protected]>
> wrote:
>
> Compilers do that with what is called loop rotation optimization.
>
> On 4/22/2024 3:59 PM, Chuck Guzis via cctalk wrote:
>> On 4/22/24 13:53, Paul Koning via cctalk wrote:
>>> In COMPASS:
>>>
>>> MORE SA1 A1+B2 (B2 = 2)
>>> SA2 A2+B2
>>> BX6 X1
>>> LX7 X2
>>> SB3 B3-2
>>> SA6 A6+B2
>>> SA7 A7+B2
>>> PL b3,MORE
>> My recollection is that putting the stores at the top of the loop and
>> the loads at the bottom managed to save a few cycles. Of course, you
>> have to prime the loop...
>>
>> --Chuck
>>
>